When the away team beams down at the beginning of the episode, Data pulls out his tricorder and notes that the radiation levels are safe. Is it really wise to check on this kind of thing after you beam down?

Great Moment :

None.

Body Count :

Zero.

Factoid :

This episode was the first to feature the medical tricorder.

Plotline

The Enterprise picks up a mysterious stranger who does not know who or what he is. Events become complicated when a warship arrives demanding he be turned over so they can execute him. Then things get even stranger...